(Press-News.org) The mating habits of marine turtle may help to protect them against the effects of climate change, according to new research led by the University of Exeter. Published today (25 January 2012) in the journal Proceedings of the Royal Society B, the study shows how the mating patterns of a population of endangered green turtles may be helping them deal with the fact that global warming is leading to a disproportionate number of females being born.
The gender of baby turtles is determined by the temperature of the eggs during incubation, with warmer temperatures leading to more females being born. Higher average global temperatures mean that offspring from some populations are predominantly female. This is threatening the future of some populations and there are concerns that inbreeding within groups due to a lack of males will lead to health problems.
The study focused on a population of the green turtle, Chelonia mydas, nesting in Northern Cyprus, where, due to the high summer temperatures, 95 per cent of babies are female. The study involved a team from the University of Exeter (UK), University of Lefke (Turkey) and North Cyprus Society for Protection of Turtles. Through DNA testing, they were able to ascertain the paternity of baby turtles and, contrary to what they had expected, they found a large number of mating males.
The researchers found that 28 males sired offspring with 20 nesting females: an average of 1.4 males for every female. This means that each female's offspring were sired by one or more fathers. The researchers were surprised to find no evidence that any males fathered offspring born in that season with more than one female.
The research team had thought that one single male might be breeding with multiple females. However, their results suggest that a large number of males are mating with different females at different times. This means that there is less chance of inbreeding.
The team also carried out satellite tracking to discover that males cover thousands of miles of ocean within one breeding season. This suggests they could have also been mating with females at other sites in Turkey or North Africa.
Lead researcher University of Exeter PhD student Lucy Wright said: "It is fantastic to know that there are so many males fathering offspring in this population of green turtles. There is great concern that a lack of males could lead to inbreeding in small populations of marine turtles, potentially causing a population crash. However our research suggests that there are more males out there than expected considering the female-biased hatchling sex ratios and that their mating patterns will buffer the population against any potential feminising effects of climate change."
Corresponding author Dr Annette Broderick added: "Climate change remains a great threat to marine turtles, but our ongoing research will help us focus on where the priority areas are for management that may help them cope with future change."
INFORMATION:
The work was funded by a NERC studentship with additional support from NERC Biomolecular Analysis Facility, Sheffield.
Turtles' mating habits protect against effects of climate change
2012-01-25
ELSE PRESS RELEASES FROM THIS DATE:
Eliminating Credit Card Debt When Filing for Bankruptcy in New Jersey
2012-01-25
New Jersey families continue to suffer through the greatest economic downturn since the Great Depression. Many unemployed workers still cannot find work and their debt only "snow-balls" - often to the point where it is impossible to get out from underneath it. For many of these struggling families, the only option they can turn to for assistance during these dire times is bankruptcy.
Often individuals consider bankruptcy as a response to mounting credit card debt. Generally, credit card debt is one of the largest unsecured debts held by most people filing for ...
New migraine clinical trial guidelines
2012-01-25
Los Angeles, CA – Experts from the International Headache Society (IHS) have developed new recommendations for conduct of acute and preventive migraine clinical trials. The third edition of Migraine Clinical Trials Guidelines is now available in the IHS journal Cephalalgia, which is published by SAGE.
The new guidelines represent an expert consensus summary, and recommend a contemporary, standardized, and evidence-based approach to investigators conducting and reporting randomised, controlled migraine clinical trials.
Migraine clinical research has increased exponentially ...
Teen passengers: 'The other distraction' for teen drivers
2012-01-25
– A pair of studies by The Children's Hospital of Philadelphia (CHOP) and State Farm® identify factors that may lead teens to drive with multiple peer passengers and, then, how those passengers may affect their driver's behavior just before a serious crash. The studies were published today in the Journal of Adolescent Health.
Experts have long known that peer passengers increase teen driver crash risk. What hasn't been well understood was how they increase crash risk. "These studies help us understand the factors that may predispose teens to drive with multiple friends ...
Supporting primary children's understanding of physics
2012-01-25
New software has significant benefits for primary school children and their understanding of elementary physics, research shows. Studies funded by the Economic and Social Research Council (ESRC) focused on what primary school children know when they begin studying physics, and how much they still have to learn. The studies looked at how much children understand about the movement of objects such as direction and speed.
The studies show that the tasks used in schools to assess how children understand the movement of objects seriously underestimate how much they know already. ...
Food fried in olive or sunflower oil is not linked to heart disease
2012-01-25
Eating food fried in olive or sunflower oil is not linked to heart disease or premature death, finds a paper published on bmj.com today.
The authors stress, however, that their study took place in Spain, a Mediterranean country where olive or sunflower oil is used for frying and their results would probably not be the same in another country where solid and re-used oils were used for frying.
In Western countries, frying is one of the most common methods of cooking. When food is fried it becomes more calorific because the food absorbs the fat of the oils.
While ...
'Speed gene' in modern racehorses originated from British mare 300 years ago, scientists say
2012-01-25
Scientists have traced the origin of the 'speed gene' in Thoroughbred racehorses back to a single British mare that lived in the United Kingdom around 300 years ago, according to findings published in the scientific journal Nature Communications.
The origin of the 'speed gene' (C type myostatin gene variant) was revealed by analysing DNA from hundreds of horses, including DNA extracted from the skeletal remains of 12 celebrated Thoroughbred stallions born between 1764 and 1930.
"Changes in racing since the foundation of the Thoroughbred have shaped the distribution ...
Cocoa could prevent intestinal pathologies such as colon cancer
2012-01-25
A new study on living animals has shown for the first time that eating cocoa (the raw material in chocolate) can help to prevent intestinal complaints linked to oxidative stress, including colon carcinogenesis onset caused by chemical substances.
The growing interest amongst the scientific community to identify those foods capable of preventing diseases has now categorized cocoa as a 'superfood'. It has been recognised as an excellent source of phytochemical compounds, which offer potential health benefits.
Headed by scientists from the Institute of Food Science and ...
Study Finds Aging Baby Boomer Generation Without Living Wills
2012-01-25
To many, planning for their death or the event of incapacitation is simply superstitious or morbid. Passing away without an end of life plan, unfortunately, is all too common. However, in the wake of the aging baby boomer generation (those born between 1946 and 1964), having a living will or plan in place is more important than ever. Unfortunately, according to the Associated Press, it is estimated that roughly 64 percent of boomers do not have one.
What is a Living Will?
A living will is a document created by individuals who outline specific medical care instructions ...
GABA deficits disturb endocannabinoid system
2012-01-25
Philadelphia, PA, January 24, 2012 – Changes in the endocannabinoid system may have important implications for psychiatric and addiction disorders. This brain system is responsible for making substances that have effects on brain function which resemble those of cannabis products, e.g., marijuana.
The endocannabinoid system is of particular interest in the field of schizophrenia research because exposure to cannabis products during adolescence and young adulthood appears to increase the risk for developing schizophrenia. Also, in studies examining brain tissue collected ...
Understanding causes of obesity in Aboriginal children
2012-01-25
Ottawa, Ontario –To fully understand the causes of the obesity epidemic in Aboriginal children requires an understanding of the unique social and historical factors that shape the Aboriginal community. A review article published in Applied Physiology, Nutrition, and Metabolism emphasizes that early childhood obesity prevention efforts should begin focusing with the parents before and during pregnancy and on breastfeeding initiatives and nutrition in the early childhood development stages.
"There needs to be a focus on improving the risk factors such as income and education" ...